Jer 7:16

“Just as God knows how to heal, so does he furthermore know how to smite. He knows how to make peace but likewise permits evils. He prefers repentance but moreover commands Jeremiah not to pray for the reversal of ills on behalf of the sinful people. He says, "If they will fast, I still will not listen to their plea." And again: "Do not pray to me on behalf of the people, and do not request on their behalf in prayer and supplication, since I will not listen to them in the time when they shall have invoked me, in the time of their affliction." And further he, the same One who prefers mercy above sacrifice, says, "And do not pray to me on behalf of this people, and do not request that they may obtain mercy, and do not approach me on their behalf, since I will not listen to them in the time wherein they shall have invoked me, in the time of their affliction."”

“Rightly, then, is it said, "Who shall entreat for him?" It implies that it must be such a one as Moses to offer himself for those who sin. Or such as Jeremiah, who, though the Lord said to him, "Pray not for this people," yet prayed and obtained their forgiveness. For at the intercession of the prophet and the entreaty of so great a seer, the Lord was moved. And Jerusalem, which had meanwhile repented for its sins, had said, "O Almighty Lord God of Israel, the soul in anguish and the troubled spirit cries to you. Hear, O Lord, and have mercy."”

“He did the same thing in explaining himself to Noah about the flood that he did to Ezekiel when while living in Babylon he caused him to see the people's evil deeds in Jerusalem. And when he told Jeremiah not to pray, there too he explained himself adding, "Do you not see what they do?" And he does the same thing everywhere as he does here [in Matthew]. For what does he say? "The people of Nineveh shall rise up and shall condemn this generation, because they repented at the preaching of Jonah, and, behold, a greater one than Jonah is here."”

“[Daniel 9:2] "I, Daniel, understood by the books the number of the years concerning which the word of the Lord had come to the prophet Jeremiah, that seventy years would be accomplished for the desolation of Jerusalem." Jeremiah had predicted seventy years for the desolation of the Temple (Jeremiah 29:1-10), at the end of which the people would again return to Judaea and build the Temple and the city of Jerusalem. But this fact did not render Daniel careless, but rather encouraged him to pray that God might through his supplications fulfil that which He had graciously promised. Thus he avoided the danger that carelessness might result in pride, and pride cause offense to the Lord. Accordingly we read in Genesis that prior to the Deluge one hundred and twenty years were appointed for men to come to repentance (Genesis 6:3); and inasmuch as they refused to repent even within so long an interval of time as a hundred years, God did not wait for the remaining twenty years to be fulfilled, but brought on the punishment earlier which He had threatened for a later time. So also Jeremiah is told, on account of the hardness of the heart of the Jewish people: "Pray not for this people, for I will not hearken unto thee" (Jeremiah 7:16). Samuel also was told: "How long wilt thou mourn over Saul? I also have rejected him" (1 Samuel 16:1). And so it was with sackcloth and ashes that Daniel besought the Lord to fulfil what He had promised, not that Daniel lacked faith concerning the future, but rather he would avoid the danger that a feeling of security might produce carelessness, and carelessness produce an offense to God.”

“(Verse 16.) Therefore, do not pray for this people, nor take on their praise and prayer (or do not ask to obtain mercy for them). And do not resist me, for I will not listen to you. So that it may not seem that the Prophet does not obtain what he asks for, God commands that he not pray for the sinful people who do not repent. And when he says, 'And do not resist me,' he shows that the prayers of the saints can resist God's wrath. And the Lord spoke to Moses: Let me alone, that I may destroy this people: and I will make thee into a great nation (Exod. XXXII, 10). And in the psalms it is written: And Phinehas stood up and appeased him, and the shaking ceased, and it was counted to him for justice (Psal. CV, 30). And Aaron, having taken the censer, stood in the midst between the living and the dead, and the wrath of God ceased. And lest we think that God is cruel, who does not even allow himself to be asked, he gives reasons why he does not listen (Num. XVI), saying:”